Hypogonadism is a condition that occurs when a man’s testicles do not produce an adequate supply of testosterone. Primary hypogonadism occurs when there is an abnormality in the testicles themselves. Secondary hypogonadism occurs when there is a problem with the pituitary gland in the brain, which sends chemical messages to the testicles to produce testosterone.
Hypogonadism can occur during fetal development, at puberty, or in adult men. When it occurs in adult men, hypogonadism may cause the following problems:
- Erectile dysfunction, or the inability to achieve or maintain an erection
- Decreased sex drive
- Decrease in beard and growth of body hair
- Decrease in size or firmness of the testicles
- Decrease in muscle mass and an increase in body fat
- Enlarged male breast tissue
- Mental and emotional symptoms similar to those of menopause in women, such as hot flashes, mood swings, irritability, depression, and fatigue
Hypogonadism can be caused by a variety of factors, including:
- Klinefelter’s syndrome
This condition involves the presence of abnormal sex chromosomes. A man normally has one X chromosome and one Y chromosome. The Y chromosome contains the genetic material with the codes that determine the male gender, and related masculine characteristics and development. Men with Klinefelter’s syndrome have an extra X chromosome, which causes abnormal development of the testicles.
- Undescended testicles
Normally, the testicles develop inside the abdomen and move down into the scrotum before birth. However, in some cases, this does not happen. Usually the testicles descend by the child’s first birthday. An undescended testicle that remains outside the scrotum throughout childhood can result in hypogonadism. A testicle that remains undescended may require surgical removal due to an increased risk of cancer in the future.
Hemochromatosis, or too much iron in the blood, can cause the testicles or the pituitary gland to malfunction.
- Testicular trauma
Damage to the testicles can affect the production of testosterone, leading to hypogonadism.
- Cancer treatment
Chemotherapy or radiation therapy — common treatments for cancer — can interfere with testosterone and sperm production by the testicles, leading to hypogonadism.
- Normal aging
Older men generally have lower levels of testosterone, although the decline of the hormone varies greatly among men. For some men, the decreased testosterone production can cause hypogonadism.
- Pituitary disorders
Problems affecting the pituitary gland, including a head injury or pituitary tumor, can interfere with the gland’s signals to the testicles to produce testosterone.
Certain drugs can affect testosterone production. Commonly used psychiatric drugs and some medicines used to treat gastroesophageal reflux disease (GERD) may cause hypogonadism.
The treatment for hypogonadism depends on the specific cause of the condition. Testosterone replacement therapy can be used to treat disorders of the testicles. If the problem is related to the pituitary gland, pituitary hormones may increase testosterone levels and sperm production.